Proximity sensing devices are devices that produce an output based upon a distance between two or more sensors or objects. Proximity sensors typically contain electrical circuits having an electrical, mechanical, or optical distance sensing portion. Electromechanical sensors are often used to establish contact between two objects, such as an end switch, and electrical sensors are frequently used when a distance measurement is desired. Electrical proximity sensors commonly include inductance sensors, which rely on unique electrical properties of inductance circuits to detect the proximity of a target object.
Proximity sensors are prevalent in several industries, such as process management, automotive, and aviation. Their applications span a large range from traffic control to linkage actuation control. For example, proximity sensing devices are an integral and indispensable component of a modern aircraft. Knowledge that a moving surface has reached a particular location in its travel can promote proper and safe operation of various aircraft systems.